Multihull fishing vessel and method of use

ABSTRACT

The invention is directed to a fishing vessel and a method of menhaden fishing. The fishing vessel comprises catamaran or multi-hulled type boat or ship used as a purse boat. The fishing vessel is outfitted with a jet propulsion drive system and also has various equipment necessary for handling the purse seine, such as with an articulated crane necessary to manipulate the seine or fishing net and partially lift it out of the water, a purse winch, and a tom winch. The fishing vessel can be transported by a steamer boat and once in the fishing area is launched or it can be navigated to the fishing grounds. Once the fish are caught, the fish are unloaded from the seine or fishing net using a vacuum transfer device and stored in a refrigerated storage area on the steamer.

TECHNICAL FIELD

This invention relates to an improved boat design and method of fishing for menhaden fish and, more particularly, to an improved purse boat design and method of using the improved purse boat design to fish for menhaden or similar fish.

BACKGROUND OF THE INVENTION

Traditional methods of menhaden fishing involve the use of purse boats that handle a purse seine, which is set around a school of menhaden. The purse boats are transported using steamers, which are directed to menhaden schools by spotters. The spotters can be in small airplanes or in the crow's nest of the steamer. For example, when a spotter in the crow's nest sights a menhaden school, the seine-setter uses a striker boat to follow the fish, indicate their position, and, finally, to support the corkline after the net is set. Once the steamer reaches the school, it blows its whistle twice to signal the fishermen to man the two purse boats, which are tied to its stern or carried on the steamer itself. The purse boats are joined together and tied closely to the steamer's stern. Once the purse boats are manned, the steamer sounds its whistle again to signal the release of the two boats, each of which contains half of the purse seine or net. The purse boats approach the school, separate, and quickly release the seine, thereby encircling the school. Once set, the purse line, which runs through the bottom rings of the seine, closes the bottom of the seine to purse the net. The crews haul in the ends and bottom of the net, concentrate the fish in the pouch portion of seine, which is placed against the side of menhaden steamer, and the catch is pumped or otherwise loaded into the hold of the steamer. The catch is held aboard the steamer until the steamer reaches the processing plant. The capture of fish in this manner is called making a set.

The purse seine is usually 1200 to 1500 feet in length, and approximately 75 to 125 feet in depth. Purse seines, in effect, are long, straight sections of net webbing, which extend downward from the surface when placed in water. The net is suspended in the water by means of a series of floats attached to a line, typically referred to as a “cork line,” at the top of the net. A line, called a purse line, runs through large rings, usually made of metal, spaced at intervals, along the bottom of the net.

Purse boats are typically small, open-type, monohull boats that handle the purse seine during the fishing operation. The boat with a tom weight and tom winch is usually referred to as the “captain's” boat, and the other as the “mate's” boat. These boats are up to 40 feet long, approximately 8 feet wide, and are usually constructed of aluminum. The purse seine is carried in the large open space in the aft part of each boat, with half of the net is stored on each boat. When not fishing, the boats are carried upon or towed behind the steamer which carries the fish caught by the purse boats. The steamer can also provide living quarters and other necessary accommodations for the crew. Purse boats typically have four to six crew members per boat.

In pursuing the usual steps in menhaden fishing methods, the purse seine is handled by two purse boats with eight to twelve crewmembers. To say the least, this is an extremely laborious task. Additionally, the monohull purse boat presents many disadvantages. The range from the steamer that the monohull purse boat is able to fish is limited. Thus, it is dependant on the steamer to transport it to the fishing area. The monohull purse boat is typically less stable and more difficult to fish in rough weather, leading to unsafe working conditions for the crew. Thus, the ability of the purse boats to operate efficiently and in unfavorable environmental conditions is an occasional requirement for successful fishing operations. It follows that one objective in the instant presentation is to make it possible to reduce the number of purse boats required and, in addition, thereby reducing the number of crew necessary to perform the fishing operation.

BRIEF SUMMARY OF THE INVENTION

In one aspect, the present invention provides a vessel for purse seine fishing, the vessel with a pair of laterally spaced, longitudinally extending hulls and a main deck. The vessel includes a purse winch disposed on one side of the main deck, the purse winch having at least one drum used to retrieve the purse line, a tom wench located on the main deck, the tom winch having a drum used to retrieve a tom and a crane located on the main deck, the crane including a power block.

In another aspect, the present invention provides a vessel described as described above that is comprised of a jet propulsion system. One example of the jet propulsion system is a TRAKTOR Jet 610 HT jet propulsion system and this jet propulsion can be powered by a diesel, such as a Cummins QSM11, or other engine.

In another aspect, the present invention provide a vessel as described above that includes a storage tank located with in the main deck of the vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts the main deck of the vessel and the layout of the equipment;

FIG. 2 schematically depicts an elevation view of the vessel showing the main deck, crane, and bridge deck;

FIG. 3 schematically depicts a top view of the vessel showing the equipment on the main deck in relation to the hulls; and

FIG. 4 schematically depicts the layout of the equipment located on the lower deck.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, “a” or “an” means one or more than one.

The methods and apparatus of the present invention will now be illustrated with reference to FIGS. 1 through 4. It should be understood, that these are merely illustrative and not exhaustive examples of the scope of the present invention and that variations which are understood by those having ordinary skill in the art are within the scope of the present invention.

Referring now to the drawings, the fishing vessel 100 comprises a multi-hull vessel having a main deck 12, a bridge deck 14, and is driven by two jet drives 50. The vessel includes other equipment necessary for purse seine fishing such as a purse winch 30, a tom winch 20, a tom crane 22, and a hydraulic articulating crane 40.

As shown in FIGS. 1 and 2, the various equipment necessary for purse seine fishing is located on main deck 12. The purse winch 30 is located on one side of the vessel, while tom winch 20 and tom crane 22 are located on the opposite side of the vessel. In the preferred embodiment, purse winch 30 is located on the port side of the vessel and near amidships (slightly toward the bow). Purse winch 30 also has two winding drums 32 and 34.

The vessel also includes an articulating crane, which is used in connection with power block 42 to haul the seine net. Generally, a power bock is a large powered pulley. The original power block was invented in the early 1950s, was essentially a v-shaped roller and sheave coated with hard rubber that was suspended from a davit. The pulley was powered from a simple winch that moved a rope over the sheave. Power blocks are available in many sizes and configurations and can be suspended from any structure from a simple mechanical arm to an articulated crane. In this design, power block 42 is suspended from crane 40. For example, in the preferred embodiment, crane 40 is a Palfinger PK 23500 crane, which includes six hydraulic extensions allowing it to reach out 16.7 m with a lifting capacity of 6100 kg. Other articulated or telescopic cranes could also be utilized. Crane 40 is mounted to foundation 44, which is located on main deck 12. In the preferred embodiment, crane 40 is located slightly toward the port side of the vessel and slightly abaft. This is necessary for stability of the vessel and to allow sufficient space on main deck 12 to place the tom and seine net.

The deck equipment also includes tom winch 20 and tom crane 22. A “tom” is a large lead weight (1,400 lb.) used during the pursing (closing) operation of the purse seine net. It has two fairlead sheaves that route the purse line (rope) and is dropped overboard and rests on the bottom to anchor the net. After the net is closed, the tom and rings are picked up, using tom winch 20 and placed back into the boat using tom crane 22. In the preferred embodiment, tom winch 20 and tom crane 22 are located on the starboard side of the vessel and near midship.

In designing a vessel, space is a premium. This often leads to crowded decks and spaces. To alleviate this problem, storage tanks are located within main deck 12. In the preferred embodiment, main deck 12, is approximately two foot thick. Thus, a tank can be built within main deck 12. The vessel requires fuel oil, or diesel, to power the engines and hydraulic fluid to power various equipment, such as the purse winch and tom crane. To accommodate this, two tanks are built into main deck 12. In the preferred embodiment, fuel oil tank 56 and hydraulic oil tank 58 are located within main deck 12. For stability reasons, tanks 56 and 58 are designed and located between the two hulls and toward the bow of the vessel.

In the preferred embodiment, the multihulled vessel consists of two hulls, or vakas, which is commonly referred to as a catamaran. The vessel is propelled by two jet drives 50 powered by diesel engines. In the preferred embodiment, the jet drive is a TRAKTOR Jet 610 HT; however, any properly sized jet drive could be utilized. This jet is designed to produce high thrust jet propulsion necessary for the seine fishing operations. One jet drive is located in starboard side hull 72 and one jet drive is located in port side hull 74. The thrust of individual jet drives 50 are controlled to navigate the vessel. There are two means for accomplishing this. First, jet drives 50 include two outlet nozzles that are used to direct the water jet. Since the nozzles are located at the stern of the vessel, they are turned in the direction that you want the bow of the vessel to go. So if you want to turn port, the nozzles are pointed to the port side of the vessel. Alternatively, the thrust of the jet drives can also be varied to navigate the vessel. In this case, if you want the vessel to turn port, you would increase the thrust to the jet on the starboard side of the vessel. Jet drives 50 are powered by a Cummins QSM11 diesel engine 52; however, any properly sized diesel engine could be utilized. Additionally, other engines, such as gasoline, are also envisioned. Engine 52 is a six cylinder engine that produces approximately 600 horsepower at 2300 rpm. Engine 52 is connected to jet drive 50 with a gear box 54.

Additionally, the vessel includes an electric generator 60 and a hydraulic pump 62. The electric generator provides necessary electrical power to the vessel. Use of the generator 60 also allows the boat's weight to be minimized. Hydraulic pump 62 provides hydraulic power to various equipment, such as purse winch 30. In the, preferred embodiment, hydraulic pump 62 is driven by an auxiliary diesel engine. However, hydraulic pump 62 could also be driven by diesel engine 52.

As discussed in the background section, typical purse boats are transported to the fishing area using a steamer. This is mainly because typical purse boats have neither the speed nor the range to allow it to sail to the fishing area. Vessel 100, however, with its multihull design and jet drive, has both the speed and range to allow it to sail to the fishing areas. Yet, even with its faster speed and longer range, there are times when it is advantageous to transport vessel 100 using a steamer. To accommodate this, vessel 100 is configured with lifting eye 16. The lifting eye is a reinforced section at the bow of the boat that allows vessel 100 to be raised out of the water and secured on the steamer.

When vessel 100 and the steamer have reached the fishing grounds, the vessel 100 and the steamer will work with the spotter to find and catch the school of fish. As discussed in the background section, the spotter can be in the steamer, an airplane, or can use any other means, such as sonar, to find the school of fish. Once the spotter locates the school of fish, he will direct vessel 100 to the school of fish.

Up to this point, use of vessel 100 has been similar to that of typical fishing with purse boats. That is, the vessel and the steamer travel to the fishing ground and the vessel travels to the location of the school of fish at the direction of a spotter. However, unlike typical purse seine net fishing, which uses two purse boats, each deploying half of the net, the present invention requires only one vessel. Thus, there are many differences in how vessel 100 is used when compared to the prior art.

First, unlike typical purse seine net fishing where half the net is in each purse boat, all of the net is in vessel 100. Thus, when the net is deployed, the first end of the next entering the water must be anchored to allow vessel 100 to encircle the school of fish. While this can be accomplished by any anchoring means, the preferred embodiment of the invention uses a sea anchor. A sea anchor is any object that is dragged in the water to prevent drifting. One example of a sea anchor is a canvas covered conical frame. The sea anchor is attached to the first end of the purse seine net as it is deployed into the water.

The spotter will then direct the boat to the location of the school of fist. Once in location, the crew on board vessel 100 will begin to deploy the purse seine net. Another difference between the present invention and typical purse seine fishing should also be noted here. In typical purse seine fishing, the net is typically set with the wind and with the current; however, in the present invention, the preferred method is to initially set the net into the wind and into the current.

Once the net is introduced into the water, vessel 100 proceeds in a generally circular path around the school of fish until the net has been fully deployed and encircled around the school of fish. The remaining operations are similar to traditional purse seine net fishing. Examples of these operations can be found in U.S. Pat. No. 4,125,955, which is incorporated by reference herein. Once the net has been played out, the “tom” is dropped to anchor and close the bottom of the net to form a “purse.”

After the purse line has been pursed and the cork line has been winched in, power block 42 is then used to progressively raise and gather the net for stacking on main deck 12. Once the fish have been concentrated within the purse, the steamer will navigate to the purse seine. The fish in the purse are then transported into the steamer using a transfer pumping system. This can submersible on-line centrifugal pump through which the fish must pass. Other transfer systems, such as the system described in U.S. Pat. No. 4,558,990 and No. 4,442,786, which are incorporated by reference herein, can also be used. Once on board the steamer the fish are stored in a refrigerated storage area until the steamer reaches a processing facility.

Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. 

What is claimed is:
 1. A vessel for purse seine fishing, the vessel comprising: a pair of laterally spaced, longitudinally extending hulls, a main deck; a purse winch disposed on one side of the main deck, the purse winch having at least one drum used to retrieve the purse line; a tom winch located on the main deck, the tom winch having a drum used to retrieve a tom; and a crane located on the main deck, the crane including a power block.
 2. The vessel of claim 1 further comprising a jet propulsion system.
 3. The vessel of claim 2, wherein the jet propulsion system is a TRAKTOR Jet 610 HT jet propulsion system.
 4. The vessel of claim 2, wherein the jet propulsion system is powered by a diesel engine.
 5. The vessel of claim 2, wherein the jet propulsion system is powered by a gasoline engine.
 6. The vessel of claim 4, wherein the diesel engine is a Cummins QSM11 diesel engine.
 7. The vessel of claim 1, further comprising a fuel storage tank, wherein the fuel storage take is located within the main deck of the vessel.
 8. The vessel of claim 1, wherein the purse winch is located on the port side of the vessel.
 9. The vessel of claim 8, wherein the tom winch is located on the starboard side of the vessel. 